CN1646974A - Backlight assembly for liquid crystal display apparatus - Google Patents

Abstract

The invention discloses a backlight assembly (500) for an LCD device. The backlight assembly (500) includes a light guide plate (300) for emitting light in two directions (325, 335) and a brightness control member (400) for controlling the brightness ratio of the light beams emitted in the two directions. Therefore, the LCD device can display the same or different images from each other in two directions using the brightness control member (400).

Description

Backlight assembly for liquid crystal display device

technical field

The present invention relates to a backlight assembly and an LCD (liquid crystal display) device, and more particularly to a backlight assembly capable of displaying image information in two directions different from each other for emitting light in a plurality of directions, and a backlight assembly having the backlight components of the LCD device.

Background technique

In general, LCD devices display images using liquid crystals in which transmittance of light varies with electric field strength. The LCD device is in the shape of a flat plate with a thickness of several millimeters to several tens of millimeters, and a liquid crystal layer contained therein has a thickness of not more than several millimeters.

LCD devices are widely used as communication devices such as cellular phones, and as display devices such as portable computers or desktop computers, and the like.

An LCD device employing a method of displaying images in only one direction has been developed so that its thickness and volume can be reduced. Recently, LCD devices that display the same or different images in two directions have been developed.

To display images in two directions, an LCD device includes a reflective plate for splitting light beams into two directions and a mirror with polarizing filter, pixel electrode, liquid crystal, two electrodes facing each other, glass substrate, polarizer LCD panels. The LCD device also includes a flat panel type light emitting part for emitting light in two opposite directions and display cells disposed on both surfaces of the light emitting part. The LCD device also includes a backlight assembly, a first LCD panel and a second LCD panel disposed on both surfaces of the backlight assembly, respectively.

The LCD device splits light to display images in two opposite directions, but the LCD device cannot control the intensity of light split in the two opposite directions.

As an example of a display device requiring control of light intensity, a cellular phone having an external display device and a built-in display device will be described below. For example, if the model "A" cellular phone has an external display device that is less bright than the internal display device, most of the light from the light source is provided to the internal display device. Also, if the model "B" cellular phone has an external display device that is brighter than the built-in display device, most of the light emitted from the light source is supplied to the external display device.

As described earlier, the LCD device can split light into two opposite directions, but the LCD device cannot variably control the amount of light split into two opposite directions according to external conditions.

Contents of the invention

The present invention provides a backlight assembly capable of splitting light into two light rays having different brightness and providing the split light rays in two directions.

The present invention also provides an LCD having a backlight assembly capable of splitting light into two light rays having different brightness and displaying the same or different images from each other in two directions.

In one aspect of the present invention, there is provided a backlight assembly for emitting light in two directions, comprising: a light guide plate having a light incident surface, a first light exit surface and a second light exit surface, wherein the light incident surface The first light input from between the first display area and the second display area is converted into a second light, and the first light exit surface emits a part of the second light as a third light to the first display area, and the second light exit surface emitting the remaining part of the second light as fourth light to the second display area, the light guide plate being disposed between the first display area and the second display area; and a brightness control part for reflecting a part of the fourth light to The first display area transmits the remaining part of the fourth light to the second display area, so that the first brightness of the first display area and the second brightness of the second display area respectively have a predetermined brightness ratio.

On the other hand, the present invention also provides a backlight assembly for emitting light in two directions, comprising: a lamp assembly disposed between the first display area and the second display area, for displaying The first light and the fifth light are provided between the regions, and the first and fifth light have different paths from each other; the first light guide plate has a first light incident surface that changes the first light into a second light, and converts the second light into the second light. A part of the third light is reflected to the first surface of the first display area and the second surface emitting the third light, and the second surface faces the first surface; the second light guide plate has the function of changing the fifth light into the sixth light The second light incident surface, the third surface that reflects a part of the sixth ray as the seventh ray to the second display area, and the fourth surface that emits the seventh ray, the fourth surface faces the third surface; a reflector between the third surface, used to reflect the remaining part of the second light leaked from the first surface as the fourth light to the first display area, and reflect the remaining part of the fifth light leaked from the third surface Part of it is reflected to the second display area as the eighth light.

In another aspect, there is provided an LCD device, comprising: a lamp assembly disposed between a first display area and a second display area for providing first light between the first and second display areas; a light guide plate , has a light incident surface, a first light exit surface and a second light exit surface, wherein the light incident surface converts the first light into a second light, and the first light exit surface emits a part of the second light as a third light to the first In the display area, the second light exit surface emits the remaining part of the second light as the fourth light to the second display area; the brightness control part is used to reflect a part of the fourth light to the first display area, and the fourth light The remaining part of is transmitted to the second display area, so that the first brightness of the first display area and the second brightness of the second display area respectively have a predetermined brightness ratio; the first LCD panel assembly is used to convert the third and fourth light A part of the fourth light becomes the first display light with image information; and the second LCD panel assembly is used for changing the remaining part of the fourth light into second display light with image information.

In another aspect, an LCD device is provided, comprising: a lamp assembly disposed between a first display area and a second display area for providing a first light and a fifth light between the first and second display areas The light rays, the first and fifth light rays have paths different from each other; the first light guide plate has a first light incident surface for changing the first light rays into second light rays, and for turning a part of the second light rays into third light rays reflect to the first display area and transmit the remaining part of the second light as the fourth light to the first surface of the second display area and the second surface facing the first surface for emitting the third light; the second light guide plate , has a second light incident surface that turns the fifth ray into a sixth ray, reflects a part of the sixth ray as the seventh ray to the second display area and transmits the remaining part of the sixth ray as the eighth ray to the first The third surface of the display area, and the fourth surface facing the third surface for emitting the seventh light; the reflection plate arranged between the first and the third surface is used to reflect the second light leaked from the first surface The remaining part of the light is reflected to the first display area as the fourth light and the remaining part of the fifth light leaked from the third surface is reflected to the second display area as the eighth light; the first LCD panel assembly is used for using the third and the fourth light to generate first display light with image information; and a second LCD panel assembly for generating second display light with image information using the seventh and eighth light.

According to a backlight assembly for an LCD device, light emitted from a light source is divided into light of a first display area and light of a second display area of the LCD device. A part of the light supplied to the second display area is reflected toward the first display area, and the remaining part of the light supplied to the second display area is transmitted, thereby controlling the luminance ratio of the first and second display areas. Therefore, desired images can be displayed in both directions.

Description of drawings

Through the following detailed description in conjunction with the accompanying drawings, the above-mentioned and other advantages of the present invention will become more clear, wherein:

1 is a schematic diagram showing a backlight assembly for emitting light in two directions according to a first embodiment of the present invention;

FIG. 2 is a schematic diagram showing a light reflection pattern disposed on the light guide plate of the backlight assembly shown in FIG. 1;

Fig. 3 is a schematic diagram showing the size and distribution of the light reflection pattern shown in Fig. 2;

4 is a diagram showing a backlight assembly for emitting light beams in two directions according to a second embodiment of the present invention;

5 is a graph showing brightness curves of a first display area and a second display area in a backlight assembly according to the present invention;

6 is a diagram showing a backlight assembly for emitting light in two directions according to a third embodiment of the present invention;

7 is a diagram showing a backlight assembly for emitting light in two directions according to a fourth embodiment of the present invention;

FIG. 8 is a schematic diagram showing a light reflection pattern provided on the light guide plate shown in FIG. 7;

FIG. 9 is a schematic diagram showing an optical sheet disposed on the backlight assembly shown in FIG. 8;

10 is a diagram showing a backlight assembly for emitting light beams in two directions according to a fifth embodiment of the present invention;

Fig. 11 is a graph representing the size and distribution of the light reflection pattern shown in Fig. 10;

Figure 12 is a curve representing the size difference between the first light reflecting pad (first light reflecting pad) shown in Figure 10 and the second light reflecting pad (first light reflecting pad);

13 is a diagram showing a backlight assembly for emitting light in two directions according to a sixth embodiment of the present invention;

FIG. 14 is a schematic diagram showing an optical sheet disposed on the backlight assembly shown in FIG. 13;

15 is a diagram showing a backlight assembly for emitting light in two directions according to a seventh embodiment of the present invention;

Fig. 16 is a graph representing the size and distribution of the light reflection pattern shown in Fig. 10;

Fig. 17 is a graph showing the size difference between the first light reflecting pad and the second light reflecting pad shown in Fig. 15;

18 is a diagram showing a backlight assembly for emitting light beams in two directions according to an eighth embodiment of the present invention;

19 is a schematic diagram showing an LCD device according to a first embodiment of the present invention;

20-23 are diagrams showing the sizes and positions of the first LCD panel assembly and the second LCD panel assembly shown in FIG. 19;

24 and 25 are diagrams representing driving methods of the first and second LCD panel assemblies shown in FIG. 19;

26 is a schematic diagram showing an LCD device according to a second embodiment of the present invention; and

FIG. 27 is a diagram showing the sizes and positions of the first LCD panel assembly and the second LCD panel assembly shown in FIG. 26. Referring to FIG.

Detailed ways

FIG. 1 is a diagram showing a backlight assembly for emitting light in two directions according to a first embodiment of the present invention.

Referring to FIG. 1 , the backlight assembly 500 includes a light guide plate 300 and a brightness control member 400 . The light guide plate 300 has a cuboid shape and is disposed between the first display area 100 and the second display area 200 . The light guide plate 300 includes four side surfaces, namely a light incident surface 310 , a first light exit surface 320 and a second light exit surface 330 .

In particular, the first and second light exit surfaces 320 and 330 face each other and are respectively in the shape of a cuboid. The first light exit surface 320 is coupled to the second light exit surface 320 through four side surfaces including the light incident surface 310 , which are perpendicular to the first and second light exit surfaces 320 and 330 .

The light incident surface 310 of the light guide plate 300 receives the first light 305 from the outside. The first light 305 is emitted from a point light source such as LED or a line light source such as CCFL. The light source emitting the first light is indicated by reference numeral "301".

The first light rays 305 are transformed into second light rays during passage through the light entrance surface 310 , wherein the light entrance surface 310 has a medium different from the air between the light source 301 and the light entrance surface 310 . The second light 315 is reflected inside the light guide plate 300 according to the law of refraction and emitted from the light guide plate 300 in two directions. Light corresponding to a part of the second light 315 is emitted from the first light emitting surface 320 to the first display area 100 . The light emitted from the first light emitting surface 320 to the first display area 100 is defined as the third light 325 .

Light rays corresponding to the rest of the second light rays 315 are emitted from the second light emitting surface 330 to the second display area 200 . The light emitted from the second light emitting surface 330 and provided to the second display area 200 is defined as a fourth light 335 .

Therefore, the first light 305 may be provided to the first and second display areas 100 and 200 using the light guide plate 300 .

However, it is difficult to control the first luminance at the first display area and the second luminance at the second display area using only the light guide plate 300 . To control the first and second luminances, the light guide plate 300 must be redesigned and remanufactured.

In the present invention, the brightness control member 400 controls first and second brightness at the first and second display areas 100 and 200 . The brightness control member 400 reflects a part of the fourth light 335 to the first display area 100 and transmits the rest of the fourth light 335 to the second display area 200 .

The brightness control member 400 is in the shape of a sheet or a plate, and is made of PET (polyethylene terephthalate) resin. The brightness control member 400 may be fabricated to reflect about 80% of the fourth light 335 and transmit about 20% of the fourth light 335 , or to reflect about 20% of the fourth light 335 and about 80% of the fourth light 335 . The brightness control member 400 may be manufactured using materials that partially reflect and transmit light.

FIG. 2 is a schematic diagram showing light reflection patterns provided on the light guide plate of the backlight assembly shown in FIG. 1, and FIG. 3 is a diagram showing the size and distribution of the light reflection patterns shown in FIG. 2. Referring to FIG.

Referring to FIGS. 2 and 3 , the light guide plate 300 includes a plurality of light reflective pads 331 disposed on the second light emitting surface 330 facing the brightness control member 400 . The light reflection pad 331 in contact with the second light emitting surface 330 reflects a part of the second light 315 to the first light emitting surface 320 .

The light reflection pads 331 are disposed on the second light emitting surface 320 in a matrix structure. The light reflective pad 331 is formed on the second light emitting surface 320 by a screen printing method. The planar size of the light reflective pad 331 becomes larger as the light reflective pad 331 moves away from the light incident surface 310 . Changing the planar size of the light reflective pad 331 is used to uniformly maintain the reflection amount of the fourth light 335 through the light reflective pad 331 disposed on the second light emitting surface 330 .

As shown in FIG. 2 , the first light emitting surface 320 is parallel to the second light emitting surface 330 .

4 is a diagram showing a backlight assembly for emitting light in two directions according to a second embodiment of the present invention. 5 is a graph showing brightness of a first display area and a second display area in a backlight assembly according to the present invention. 6 is a diagram showing a backlight assembly for emitting light beams in two directions according to a third embodiment of the present invention.

Referring to FIG. 4 , the first light exit surface 320 is not parallel to the second light exit surface 330 . In particular, the thickness of the first and second light exiting surfaces 320 and 322 is the thickest at the light incident surface 310 , and gradually becomes thinner as the first and second light exiting surfaces 320 and 322 move away from the light incident surface 310 .

Referring to FIG. 5 , the first luminance at the first display area 100 is higher than the second luminance at the second display area 200 . To obtain the result that the first brightness is higher than the second brightness, it is necessary to control the brightness control member 400 to have a light reflectance higher than a light transmittance with respect to the fourth light ray 335 . Similarly, to obtain the result that the second brightness in the second display area 200 is higher than the first brightness in the first display area 100, it is necessary to control the brightness control member 400 to have a light transmittance higher than the light reflectance with respect to the fourth light ray 335 Rate.

As shown in FIG. 6 , to improve the optical properties of the light guide plate 300 , an optical sheet 340 may be disposed on the first light emitting surface 320 of the light guide plate 300 .

The optical sheet 340 includes a diffusion sheet 342 and a prism sheet 344 . The diffusion sheet 342 diffuses the third light 325 and part of the fourth light 355 reflected from the brightness control member 400 to provide light with uniform brightness to the first display area 100 .

The prism sheet 344 disposed on the diffusion sheet 342 controls the direction of the light emitted through the diffusion sheet 342 to provide light with an improved viewing angle. In particular, the prism sheet 344 includes a plate-shaped main body portion 344 a and a brightness enhancement portion 344 b for enhancing brightness, and the brightness enhancement portion 344 b is disposed facing the first light exit surface 320 . The brightness enhancement part 344b is continuously provided on and protruded from the main body part 344a, and has a triangular cross section.

FIG. 7 is a diagram showing a backlight assembly for emitting light in two directions according to a fourth embodiment of the present invention.

Referring to FIG. 7 , the backlight assembly 100 includes a first light guide plate 700 , a second light guide plate 800 , a lamp assembly 940 and a brightness control member 900 .

The lamp assembly 940 includes a lamp 950 and a lamp reflector 930 . The lamp 950 may include LEDs as point light sources or CCFLs as line light sources. The light incident from the light source to the first light guide plate 700 is defined as a first ray 952 , and the light incident from the light source to the second light guide plate 800 is defined as a fifth ray 956 .

The lamp reflector 930 radially reflects the light emitted from the lamp 950 to provide the light in a direction in which the first and fifth light rays 952 are provided. The lamp reflector 930 includes first and second side surfaces 932 and 934 and a joining side surface 936 joining the first side surface 932 to the second side surface 934 . The first and second side surfaces 932 and 934 and the joining side surface 936 have higher reflectivity than the outer surfaces thereof. The first and second light guide plates 700 and 800 are disposed between the first and second side surfaces 932 and 934 .

The first light guide plate 700 has a cuboid shape and is disposed between the first display area 100 and the second display area 200 . The first light guide plate 700 includes four side surfaces including a first light incident surface 710 , a first surface 720 and a second surface 730 .

The first and second surfaces 720 and 730 are respectively in the shape of a cuboid. The first and second surfaces 720 and 730 are coupled to each other by four side surfaces.

The first light incident surface 710 of the first light guide plate 700 receives the first light from the lamp 950 . The first light 952 becomes the second light 953 while passing through the first light incident surface 710 . The first surface 720 reflects part of the second light 952 satisfying the reflection condition to the first display area 100 according to the law of refraction. The remaining part of the second light ray 953 that does not satisfy the reflection condition of the law of refraction leaks into the second display area 200 .

Below, the part of the second light 953 reflected to the first display area 100 is defined as the third light 954 , and the rest of the second light 953 transmitted to the second display area 200 is defined as the fourth light 955 .

The second light guide plate 800 is in the shape of a cuboid. The second light guide plate 800 is disposed between the first display area 100 and the second display area, adjacent to the first surface 720 of the light guide plate 700 . In addition, the first and second light guide plates 700 and 800 are parallel to each other. The second light guide plate 800 includes four side surfaces including a second light incident surface 810 , a third surface 820 and a fourth surface 830 . The fourth side surface joins the third side surface 820 to the fourth surfaces 820 and 830 of the second light guide plate 800 . The fourth surface 830 has the same shape as the third surface 820 .

The second light incident surface 810 of the light guide plate 800 receives the fifth light 956 from the etc. 950 . The fifth ray 956 becomes a sixth ray 957 while passing through the second light incident surface 810 . The third surface 820 reflects a part of the sixth light 957 satisfying the reflection condition of the law of refraction toward the second display area 200 . The remaining part of the sixth light ray 957 that does not satisfy the reflection condition of the law of refraction leaks into the second display area 200 .

Hereinafter, the part of the sixth light 957 reflected to the second display area 200 is defined as the seventh light 958 , and the remaining part of the sixth light 957 transmitted to the first display area 100 is defined as the eighth light 959 .

A brightness control member 900 as a reflection plate 900 is disposed between the first and second light guide plates 700 and 800 . The reflection plate 900 is in the shape of a sheet or a plate made of PET resin. The reflection plate 900 reflects the fourth light 955 leaked from the first surface 720 of the first light guide plate 700 to the first display area 100, and reflects the eighth light 959 leaked from the third surface 820 of the light guide plate 800 to the second display area 100. Display area 200 .

The operation of the backlight assembly 1000 is described below with reference to FIG. 7 .

The first and fifth light rays 952 and 956 emitted from the lamp 950 of the lamp assembly 940 are input to the first and second light incident surfaces 710 and 810 of the first and second light guide plates 700 and 800, respectively. The first ray 952 becomes the second ray 953 .

Part of the second light 953 satisfying the reflection condition of the law of refraction is reflected by the first surface 720 and provided to the first display area 100 as the third light 954 via the second surface 730 . The remaining part of the second light 953 satisfying the transmission condition of the law of refraction is provided to the second display area 100 as the fourth light 955 via the first surface 720 .

The fifth light 956 emitted from the lamp 950 of the lamp assembly 940 becomes a sixth light 957 . Part of the sixth light 957 satisfying the reflection condition of the law of refraction is reflected by the third surface 820 and provided to the second display area 200 as the seventh light 958 via the fourth surface 830 . The remaining part of the sixth light 957 that does not satisfy the reflection condition of the law of refraction is provided to the first display area 100 as the eighth light through the third surface 820 .

The third and seventh light rays 954 and 958 are provided to the first and second display areas 100 and 200 through the first and second light guide plates 700 and 800 . The fourth and eighth light rays 954 and 958 leak to the first and second light guide plates 700 and 800 .

The fourth and eighth light rays 955 and 959 are reflected from the reflection plate 900 to provide the fourth and eighth light rays 955 and 959 to the first and second display areas 100 and 200, respectively.

In the backlight assembly 1000 , the first surface 720 of the first light guide plate 700 is parallel to its second surface 730 , and the third surface 820 of the second light guide plate 800 is parallel to the fourth surface 830 . And, the first light guide plate 700 has the same size as the second light guide plate 800 .

FIG. 8 is a schematic view showing a light reflection pattern provided on the light guide plate shown in FIG. 7, and FIG. 9 is a schematic view showing an optical sheet provided on the backlight assembly shown in FIG.

As shown in FIG. 8 , the first light guide plate 700 includes a plurality of first light reflecting pads 721 disposed on its first surface 720 , and the second light guide plate 800 includes a plurality of second light reflecting pads 721 disposed on its third surface 820 . light reflective pad 821 . The first and second light reflection pads 721 and 821 are arranged in a matrix structure.

The sizes of the first and second light reflective pads 721 and 821 become larger as the first and second light reflective pads 721 and 821 are moved away from the first and second light incident surfaces 710 and 810 , respectively.

The backlight assembly 1000 shown in FIG. 7 further includes a first optical sheet 740 and a second optical sheet 840 as shown in FIG. 9 .

Referring to FIG. 9 , the first optical sheet 740 is disposed between the first display area 100 and the first light guide plate 700 , facing the second surface 730 of the first light guide plate 700 .

The first optical sheet 740 includes a plate-shaped body part 742 and a brightness enhancement part 744 for improving brightness, which is provided on a surface facing the first surface 720 . The brightness enhancement part 744 is continuously provided on and protrudes from the main body part 742, and has a triangular cross section.

The second optical sheet 840 is disposed between the second display area 200 and the second light guide plate 800 , facing the fourth surface 830 of the second light guide plate 800 .

The second optical sheet 840 includes a plate-shaped body portion 842 and a brightness enhancement portion 844 for enhancing brightness, which is disposed on a surface facing the fourth surface 830 . The brightness enhancement part 844 is continuously provided on and protruded from the main body part 842 and has a triangular cross section.

The first optical sheet 740 enhances the optical properties of the third light 954 and part of the eighth light 959 , such as viewing angle and brightness distribution. The second optical sheet 840 enhances the optical properties of the seventh light 958 and part of the fourth light 955 , such as viewing angle and brightness distribution.

10 is a schematic diagram showing a backlight assembly for emitting light beams in two directions according to a fifth embodiment of the present invention, and FIG. 11 is a graph showing the size and distribution of light reflection patterns shown in FIG. 10; FIG. 12 is a graph showing FIG. 10 shows a graph of the size difference between the first light reflective pad and the second light reflective pad.

Referring to FIG. 10 , the first and second light guide plates 700 and 800 may be formed to have different sizes from each other. In FIG. 10 , the first light guide plate 700 has a larger size than the second light guide plate 800 .

The first light guide plate 700 includes a first light reflective pad 725 disposed on the first surface 720 thereof, and the second light guide plate 800 includes a second light reflective pad 825 disposed on the third surface 820 thereof. Where the light guide plate 700 is larger in size than the second light guide plate 800 , the first light reflective pads 725 disposed on the first surface 720 have a different pattern from the second light reflective pads 825 disposed on the third surface 820 .

As shown in FIG. 11 , the sizes of the first and second light reflective pads 725 and 825 become larger as the first and second light reflective pads 725 and 825 move away from the first and second light incident surfaces 710 and 810 , respectively. The size of the first light reflective pad 725 is different from that of the second light reflective pad 825 .

Referring to FIG. 12 , the dimensional change rate of the second light reflective pad 825 based on the distance between the second light incident surface 810 and the second light reflective pad 825 is greater than that based on the distance between the first light incident surface 710 and the first light reflective pad 725 The dimensional change rate of the first light reflective pad 725 is . In FIG. 12 , the curve denoted by reference sign “a” indicates the dimensional change rate of the first light reflective pad 725 , and the curve denoted by reference sign “b” indicates the dimensional change rate of the second light reflective pad 825 .

When the dimensions of the first and second light reflective pads 725 and 825 are measured at positions away from the first and second light incident surfaces 710 and 810 indicated by reference numeral "A", the first light reflective pad 725 has a dimension "B", the second light reflective pad 825 has a dimension "C" greater than the dimension "B".

13 is a schematic diagram showing a backlight assembly for emitting light beams in two directions according to a sixth embodiment of the present invention; FIG. 14 is a schematic diagram showing optical sheets provided on the backlight assembly shown in FIG. 13 .

Referring to FIG. 13, the first and second light guide plates 700 and 800 of the backlight assembly 1000 may be wedge-shaped. The thickness between the first and second surfaces 720 and 730 of the first light guide plate 700 is the thickest at the first light incident surface 710 , and increases as the first and second surfaces 720 and 730 move away from the first light incident surface 710 . Gradually thins. That is, the first surface 720 is inclined toward the second surface 730 . The thickness between the third and fourth surfaces 820 and 830 of the second light guide plate 800 gradually becomes thinner as the first and second surfaces 820 and 830 approach the second light incident surface 810 . That is, the third surface 820 is inclined to the fourth surface 830 and parallel to the first surface 720 . In addition, the first surface 720 of the first light guide plate 700 is parallel to the fourth surface 830 of the second light guide plate 800 .

The first light guide plate 700 includes a first light reflective pad 721 disposed on a first surface 720 thereof, and the second light guide plate 800 includes a second light reflective pad 821 disposed on a third surface 820 thereof. The sizes of the first and second light reflective pads 721 and 821 become larger as the first and second light reflective pads 721 and 821 are moved away from the first and second light incident surfaces 710 and 810 , respectively.

The backlight assembly 1000 shown in FIG. 13 may further include the first optical sheet 740 and the second optical sheet 840 shown in FIG. 14 .

Referring to FIG. 14 , the first optical sheet 740 is disposed between the first display area 100 and the first light guide plate 700 and faces the second surface 730 of the first light guide plate 700 .

The first optical sheet 750 includes a plate-shaped body portion 752 and a brightness enhancement portion 754 for enhancing brightness, which is disposed on a surface facing the first surface 720 . The brightness enhancement part 754 is continuously provided on and protruded from the main body part 752, and has a triangular cross section.

The second optical sheet 840 is disposed between the second display area 200 and the second light guide plate 800 , facing the fourth surface 830 of the second light guide plate 800 .

The second optical sheet 850 includes a plate-shaped body portion 852 and a brightness enhancement portion 854 for enhancing brightness, which is disposed on a surface facing the fourth surface 830 . The brightness enhancement part 854 is continuously provided on and protrudes from the main body part 852, and has a triangular cross section.

The first optical sheet 740 enhances the optical properties of the third light 954 and part of the eighth light 959 , such as viewing angle and brightness distribution. The second optical sheet 840 enhances the optical properties of the seventh light 958 and part of the fourth light 955 , such as viewing angle and brightness distribution.

FIG. 15 is a diagram showing a backlight assembly for emitting light in two directions according to a seventh embodiment of the present invention. FIG. 16 is a schematic diagram showing the size and distribution of the light reflection patterns shown in FIG. 10 . FIG. 17 is a graph showing a size difference between the first light reflecting pad and the second light reflecting pad shown in FIG. 15 .

Referring to FIG. 15 , the first and second light guide plates 700 and 800 may be formed to have different sizes from each other. In FIG. 15 , the first light guide plate 700 has a larger size than the second light guide plate 800 .

The first light guide plate 700 includes a first light reflective pad 721 disposed on a first surface 720 thereof, and the second light guide plate 800 includes a second light reflective pad 822 disposed on a third surface 820 thereof. Where the size of the first light guide plate 700 is larger than that of the second light guide plate 800, the first light reflective pads 721 provided on the first surface 720 have a pattern different from that of the second light reflective pads 822 provided on the third surface 820. .

As shown in FIG. 16 , the sizes of the first and second light reflective pads 721 and 822 become larger as the first and second light reflective pads 721 and 822 move away from the first and second light incident surfaces 710 and 810 , respectively. The size of the first light reflective pad 721 is different from that of the second light reflective pad 822 .

Referring to FIG. 17 , the dimensional change rate of the second light reflective pad 822 based on the distance between the second light incident surface 810 and the second light reflective pad 822 is greater than that based on the distance between the first light incident surface 710 and the first light reflective pad 721 The dimensional change rate of the first light reflective pad 721 is . In FIG. 17 , the curve denoted by reference sign “a” indicates the dimensional change rate of the first light reflective pad 721 , and the curve denoted by reference sign “b” indicates the dimensional change rate of the second light reflective pad 822 .

When the dimensions of the first and second light reflection pads 721 and 822 are measured at positions away from the first and second light incident surfaces 710 and 810 denoted by reference numeral "A", the first light reflection pad 721 has a size "E", the second light reflective pad 822 has a dimension "F" greater than the dimension "E".

FIG. 18 is a diagram showing a backlight assembly for emitting light in two directions according to an eighth embodiment of the present invention.

Referring to FIG. 18 , the backlight assembly 1000 may further include a first optical sheet 760 and a second optical sheet 860 .

The first optical sheet 760 is disposed between the first display area 100 and the first light guide plate 700 and faces the second surface 730 .

The first optical sheet 760 includes a plate-shaped body portion 762 and a brightness enhancement portion 764 for enhancing brightness, which is disposed on a surface facing the first surface 720 . The brightness enhancement part 764 is continuously provided on and protrudes from the main body part 762, and has a triangular cross section.

The second optical sheet 860 is disposed between the second display area 200 and the second light guide plate 800 , facing the fourth surface 830 .

The second optical sheet 860 includes a plate-shaped body part 762 and a brightness enhancement part 764 for enhancing brightness, which is provided on a surface facing the first surface 720 . The brightness enhancement part 764 is continuously provided on and protrudes from the main body part 762, and has a triangular cross section.

FIG. 19 is a schematic diagram showing an LCD device according to a first embodiment of the present invention. 20 to 23 are diagrams showing sizes and positions of the first LCD panel assembly and the second LCD panel assembly shown in FIG. 19. Referring to FIG.

Referring to FIG. 19 , an LCD device 1300 includes a first LCD panel assembly 1100 , a second LCD panel assembly 1200 and the backlight assembly 500 shown in FIG. 1 .

The first LCD panel assembly 1100 is disposed on the first display area 100 . The first LCD panel assembly 1100 receives the third light 325 emitted from the first light emitting surface 320 and part of the fourth light 335 reflected from the brightness control member 400 , and emits a first display light 1110 with image information.

The second LCD panel assembly 1200 is disposed on the second display area 200 . The second LCD panel assembly 1200 receives the light passing through the brightness control member 400 in the fourth light 335 emitted from the second light emitting surface 330, and emits the second display light 1210 having image information.

The first and second LCD panel assemblies 1100 and 1200 have first and second display areas, respectively. The first and second display areas are equal to each other.

In addition, the first LCD panel assembly 1100 may have a first display area different from a second display area of the second LCD panel assembly 1250, as shown in FIG. 20 .

Referring to FIG. 20 , the first display area of the first LCD panel assembly 1100 is larger than the second display area of the second LCD panel assembly 1250 .

The second display area of the second LCD panel assembly 1250 is smaller than the first display area of the first LCD panel assembly 1100 , and the driving module may be disposed in the remaining space of the second LCD panel assembly 1250 . Accordingly, the volume of the second LCD panel assembly 1250 can be reduced.

As shown in FIG. 4 , when the second light exit surface 332 of the light guide plate 300 is inclined, the second LCD panel assembly 1250 may be disposed parallel to the second light exit surface 332 . Therefore, the overall thickness of the LCD device can be reduced.

Where the first LCD panel assembly 1100 is larger than the second LCD panel assembly 1250 , the optical characteristics of the second LCD panel assembly 1250 depend on the location of the second LCD panel assembly 1250 .

In FIG. 21, reference numeral 1252 denotes a first end portion of the second LCD panel assembly 1250, and reference numeral 1254 denotes a second end portion opposite to the first end portion.

The first end portion 1252 of the second LCD panel assembly 1250 is aligned with the light incident surface 310 of the light guide plate 300 . In the case where the first end portion 1252 is aligned with the light incident surface 310 , the second LCD panel assembly 1250 can obtain more light than the case where the first end portion 1252 is not aligned with the light incident surface 310 . In addition, as shown in FIG. 21, the second LCD panel assembly 1250 may be disposed at a central portion with respect to the second light exiting surface. In addition, the second end portion 1254 of the second LCD panel assembly 1250 may be aligned with the end portion 410 of the brightness control member 400 .

24 and 25 are diagrams showing a method of driving the first and second LCD panel assemblies shown in FIG. 19. Referring to FIG.

Referring to FIG. 24, at least one of the first and second LCD panel assemblies 1100 and 1200 shown in FIG. 19 may operate by a passive matrix method without using thin film transistors. The passive matrix method is a method of generating an electric field for controlling liquid crystals using the driving signal applying part 1300 after the liquid crystals are injected between the first electrodes 1310 and the second electrodes 1320 intersecting the first electrodes 1310 .

Since the first LCD panel assembly 1100 is manipulated by the same driving signal applying part 1300 as the second LCD panel assembly 1200 is manipulated, the first LCD panel assembly 1100 displays the same image as that displayed through the second LCD panel assembly 1200 .

On the contrary, the first and second LCD panel assemblies 1100 and 1200 may respectively include a first driving module for generating a first driving signal and a second driving module for generating a second driving signal. In this case, the first LCD panel assembly 1100 displays a first image, and the second LCD panel assembly 1200 displays a second image.

As shown in FIG. 25, at least one of the first and second LCD panel assemblies 1100 and 1200 shown in FIG. 19 may be operated by an active matrix method. The active matrix method is a method of using a thin film transistor 1400 and a pixel electrode 1450 receiving power from the thin film transistor 1400 and using a driving signal applying part 1470 to generate an electric field for controlling liquid crystals.

Since the first LCD panel assembly 1100 is manipulated by the same driving signal applying part 1470 as the second LCD panel assembly 1200 is manipulated, the first LCD panel assembly 1100 displays the same image as that displayed through the second LCD panel assembly 1200 .

On the contrary, the first and second LCD panel assemblies 1100 and 1200 may respectively include a first driving module for generating a first driving signal and a second driving module for generating a second driving signal. In this case, the first LCD panel assembly 1100 displays a first image, and the second LCD panel assembly 1200 displays a second image.

FIG. 26 is a schematic diagram showing an LCD device according to a second embodiment of the present invention. FIG. 27 is a diagram showing the dimensions and positions of the first LCD panel assembly and the second LCD panel assembly shown in FIG. 26. Referring to FIG.

Referring to FIG. 26 , an LCD device 1700 includes a first LCD panel assembly 1500 , a second LCD panel assembly 1600 and a backlight assembly 1000 as shown in FIG. 7 .

The first LCD panel assembly 1500 is disposed on the first display area 100 . The first LCD panel assembly 1500 receives the third light 954 emitted from the second surface 730 and part of the fourth light 955 reflected from the brightness control member 900, and emits the first display light 1510 having image information.

The second LCD panel assembly 1600 is disposed on the first display area 200 . The second LCD panel assembly 1600 receives the eighth light 959 emitted from the third surface 830 through the brightness control member 900, and emits the second display light 1610 having image information.

The first and second LCD panel assemblies 1500 and 1600 have first and second display areas, respectively. The first and second display areas are identical to each other.

In addition, as shown in FIG. 27 , the first LCD panel assembly 1500 may have a first display area different from a second display area of the second LCD panel assembly 1600 .

Referring to FIG. 27 , the first display area of the first LCD panel assembly 1500 is larger than the second display area of the second LCD panel assembly 1600 . In case the first LCD panel assembly 1500 is larger than the second LCD panel assembly 1600 , the optical characteristics of the second LCD panel assembly 1600 depend on the location of the second LCD panel assembly 1600 .

In FIG. 27, reference numeral 1620 denotes a first end portion of the second LCD panel assembly 1600, and reference numeral 1640 denotes a second end portion opposite to the first end portion.

The first end portion 1620 of the second LCD panel assembly 1600 is aligned with the light incident surface 810 of the second light guide plate 800 . In the case where the first end portion 1620 is aligned with the light incident surface 810 , the second LCD panel assembly 1600 may obtain more light than the case where the first end portion 1620 is not aligned with the light incident surface 810 . In addition, as shown in FIG. 27 , the second LCD panel assembly 1600 may be disposed at a central portion with respect to the second light exit surface 830 . In addition, the second end portion 1640 of the second LCD panel assembly 1600 may be aligned with the end portion 910 of the brightness control member 900 .

At least one of the first and second LCD panel assemblies 1500 and 1600 shown in FIG. 26 may be operated by a passive matrix method without using thin film transistors. The passive matrix method is a method of generating an electric field for controlling liquid crystals using the driving signal applying part 1300 after the liquid crystals are injected between the first electrodes 1310 and the second electrodes 1320 intersecting the first electrodes 1310 .

Since the first LCD panel assembly 1500 is manipulated by the same driving signal applying part 1300 used to manipulate the second LCD panel assembly 1200 , the first LCD panel assembly 1500 displays the same image as that displayed through the second LCD panel assembly 1600 .

On the contrary, the first and second LCD panel assemblies 1500 and 1600 may respectively include a first driving module for generating a first driving signal and a second driving module for generating a second driving signal. In this case, the first LCD panel assembly 1500 displays a first image, and the second LCD panel assembly 1600 displays a second image.

At least one of the first and second LCD panel assemblies 1500 and 1600 shown in FIG. 26 may be operated by an active matrix method. The active matrix method is a method of using a thin film transistor 1400 and a pixel electrode 1450 receiving power from the thin film transistor 1400 and generating an electric field for controlling liquid crystal using a driving signal applying part 1470 .

Since the first LCD panel assembly 1500 is manipulated by the same driving signal applying part 1470 as that of the second LCD panel assembly 1600, the first LCD panel assembly 1500 displays the same image as that displayed through the second LCD panel assembly 1600.

On the contrary, the first and second LCD panel assemblies 1500 and 1600 may respectively include a first driving module for generating a first driving signal and a second driving module for generating a second driving signal. In this case, the first LCD panel assembly 1500 displays a first image, and the second LCD panel assembly 1600 displays a second image.

According to the present invention, the LCD device can display images in two directions, and the images in the two directions can be the same as or different from each other. In case the images are different from each other, the LCD device may display images having first and second luminances different from each other using the luminance control member. Thus, the user can obtain various images through the LCD device.

Although the embodiments of the present invention have been described above, it should be understood that the present invention is not limited to these specific embodiments, and various changes and modifications can be made to the present invention without departing from the spirit and scope of the present invention.

Claims (42)

1. backlight assembly that is used on both direction emission light comprises:

Optical plate, have light entrance face, first light-emitting face and second light-emitting face, wherein light entrance face first light that will be provided in the space between first viewing area and second viewing area is transformed into second light, first light-emitting face with a part of second light as the 3rd light emission to first viewing area, and second light-emitting face with the remainder of second light as the 4th light emission to second viewing area, this optical plate is arranged between first viewing area and second viewing area; With

The brilliance control part is used for part the 4th light is reflexed to first viewing area, and the remainder of the 4th light is transmitted to second viewing area, and first brightness that makes the viewing area of winning has the predetermined brightness ratio respectively with second brightness of second viewing area.

2. backlight assembly as claimed in claim 1, wherein, second light-emitting face comprises the light reflective pad of at least one point-like, be used for second light is reflexed to first viewing area, and along with the light reflective pad away from light entrance face, it is big that the light reflective pad becomes.

3. backlight assembly as claimed in claim 1, wherein, first and second light-emitting faces are parallel to each other.

4. backlight assembly as claimed in claim 1, wherein, optical plate is a wedge shape, its thickness is along with its attenuation away from light entrance face.

5. backlight assembly as claimed in claim 1, wherein, the brilliance control part comprises the sheet that is used to reflect with transmitted ray.

6. backlight assembly as claimed in claim 1, wherein, first brightness is greater than second brightness.

7. backlight assembly as claimed in claim 1, wherein, first light is from sending such as the pointolite of light emitting diode or such as the line source of CCFL.

8. backlight assembly as claimed in claim 1 also comprises the optical sheet of the optical characteristics that is used to improve the 3rd light, the contiguous first light-emitting face setting of optical sheet.

One kind on both direction the emission light backlight assembly, comprising:

Be arranged on the lamp assembly between first viewing area and second viewing area, be used for first light and the 5th light are provided in the space between first and second viewing areas, the first and the 5th light has the path that differs from one another;

First optical plate has first light is become first light entrance face of second light, the part of second light is reflexed to the first surface of first viewing area as the 3rd light and launches the second surface of the 3rd light, and second surface is in the face of first surface;

Second optical plate, have with the 5th light become the 6th light second light entrance face, the part of the 6th light is reflexed to the 3rd surface of second viewing area and the 4th surface of launching the 7th light as the 7th light, the 4th surface is in the face of the 3rd surface; With

Be arranged on the reflecting plate between the first and the 3rd surface, be used for the remainder of second light that leaks from first surface reflect to first viewing area as the 4th light, and handle reflects to second viewing area as the 8th light from the remainder of the 5th light of the 3rd surface leakage.

10. backlight assembly as claimed in claim 9, wherein, first and second surfaces are parallel to each other, and third and fourth surface is parallel to each other.

11. backlight assembly as claimed in claim 10, wherein, the first and the 3rd surface is included as the first smooth reflective pad and the second smooth reflective pad of point-like respectively, along with the first and second smooth reflective pad away from first and second light entrance faces, it is big that the first and second smooth reflective pad become.

12. backlight assembly as claimed in claim 10, also comprise first optical sheet that is used to improve the 3rd ray optics characteristic that is arranged in the face of the position of first surface, and be arranged on second optical sheet that is used to improve the 7th ray optics characteristic in the face of the position on the 4th surface.

13. backlight assembly as claimed in claim 10, wherein, first optical sheet comprises the first tabular main part and strengthens protuberance from first brightness of stretching out to have the triangular-section in the face of first main part of second surface, and second optical sheet comprises the second tabular main part and strengthens protuberance from second brightness of stretching out to have the triangular-section in the face of second main part on the 4th surface.

14. backlight assembly as claimed in claim 10, wherein, first optical plate has the planar dimension greater than second optical plate.

15. backlight assembly as claimed in claim 14, wherein, the first and the 3rd surface is included as the first smooth reflective pad and the second smooth reflective pad of point-like respectively, the first and second smooth reflective pad are along with it becomes away from first and second light entrance faces greatly, and the size changing rate of the second smooth reflective pad is greater than the size changing rate of the first smooth reflective pad.

16. backlight assembly as claimed in claim 9, wherein, the thickness of first optical plate is along with its attenuation near first light entrance face, and the thickness of second optical plate is along with its attenuation near second light entrance face, and second surface is parallel to the 4th surface.

17. backlight assembly as claimed in claim 16, wherein, the first and the 3rd surface is included as the first smooth reflective pad and the second smooth reflective pad of point-like respectively, and the first and second smooth reflective pad are along with they become big away from first and second light entrance faces.

18. backlight assembly as claimed in claim 16, wherein, first optical plate has the planar dimension greater than second optical plate.

19. backlight assembly as claimed in claim 18, wherein, the first and the 3rd surface is included as the first smooth reflective pad and the second smooth reflective pad of point-like respectively, the first and second smooth reflective pad are along with they become away from first and second light entrance faces greatly, and the size changing rate of the second smooth reflective pad is greater than the size changing rate of the first smooth reflective pad.

20. backlight assembly as claimed in claim 16 comprises that also the first optical sheet kind that is arranged in the face of the second surface position is arranged on second optical sheet of facing the 4th surface location place.

21. backlight assembly as claimed in claim 20, wherein, first optical sheet comprises the first tabular main part and strengthens protuberance from first brightness of stretching out to have the triangular-section in the face of first main part of second surface, and second optical sheet comprises the second tabular main part and strengthens protuberance from second brightness of stretching out to have the triangular-section in the face of second main part on the 4th surface.

22. backlight assembly as claimed in claim 9, wherein, the lamp assembly comprises:

Be used to produce the lamp of radial light; With

Be used for the light that sends from lamp is changed over the lamp reflector of the first and the 5th light, this lamp reflector is fixed on the second and the 4th surface, holds lamp simultaneously therein.

23. a LCD device comprises:

Be arranged on the lamp assembly between first viewing area and second viewing area, be used for first light is provided in the space between first and second viewing areas;

Optical plate, have light entrance face, first light-emitting face and second light-emitting face, wherein light entrance face is transformed into second light to first light, first light-emitting face with a part of second light as the 3rd light emission to first viewing area, second light-emitting face the remainder of second light as the 4th light emission to second viewing area; With

The brilliance control part is used for part the 4th light is reflexed to first viewing area, and the remainder of the 4th light is transmitted to second viewing area, and first brightness that makes the viewing area of winning has the predetermined brightness ratio respectively with second brightness of second viewing area;

The one LCD board component is used for the part of third and fourth light is become first display light with image information; With

The 2nd LCD board component is used for the remainder of the 4th light is become second display light with image information.

24. LCD device as claimed in claim 23, wherein, a LCD board component has first viewing area identical with second viewing area of the 2nd LCD board component.

25. LCD device as claimed in claim 23, wherein, a LCD board component has greater than the first identical viewing area of second viewing area of the 2nd LCD board component.

26. LCD device as claimed in claim 25, wherein, the first end of the 2nd LCD board component aligns with the light entrance face of second light-emitting face of optical plate.

27. LCD device as claimed in claim 25, wherein, the 2nd LCD board component is arranged on the core of optical plate second light-emitting face.

28. LCD device as claimed in claim 25, wherein, the sidepiece that the second end of the 2nd LCD board component is relative with the light entrance face of second light-emitting face of optical plate aligns.

29. LCD device as claimed in claim 23, wherein, at least one in the first and second LCD board components also comprises the thin film transistor plate with thin film transistor (TFT).

30. LCD device as claimed in claim 23, wherein, at least one in the first and second LCD board components also comprises the Twisted Nematic plate.

31. LCD device as claimed in claim 23, wherein, the first and second LCD board components also comprise the driver module that is used in response to drive signal displayed image information respectively.

32. LCD device as claimed in claim 23, wherein, the one LCD board component also comprises first driver module that is used for showing in response to first drive signal first information, and the 2nd LCD board component also comprises second driver module that is used for showing in response to second drive signal second information.

33. LCD device as claimed in claim 23, wherein, brilliance control partly comprises the sheet that is used to reflect with transmitted ray.

34. a LCD device comprises:

Be arranged on the lamp assembly between first viewing area and second viewing area, be used for first light and the 5th light are provided in the space between first and second viewing areas, the first and the 5th light has the path that differs from one another;

First optical plate, have be used for first light become second light first light entrance face, be used for the part of second light as the 3rd light reflection to first viewing area and with the remainder of second light as the 4th light transmission to the first surface of second viewing area and in the face of the second surface that is used to launch the 3rd light of first surface;

Second optical plate, have with the 5th light become the 6th light second light entrance face, in order to the part of the 6th light as the reflection of the 7th light to second viewing area and with the remainder of the 6th light as the 8th light transmission to the 3rd surface of first viewing area and in the face of the 4th surface that is used to launch the 7th light on the 3rd surface;

Be arranged on the reflecting plate between the first and the 3rd surface, be used for the remainder of second light that leaks from first surface as the reflection of the 4th light to first viewing area and from the remainder of the 5th light of the 3rd surface leakage as the reflection of the 8th light to second viewing area;

The one LCD board component is used to utilize third and fourth light to produce first display light with image information; With

The 2nd LCD board component is used to utilize the 7th and the 8th light to produce second display light with image information.

35. LCD device as claimed in claim 34, wherein, a LCD board component has first viewing area identical with second viewing area of the 2nd LCD board component.

36. LCD device as claimed in claim 34, wherein, a LCD board component has first viewing area greater than second viewing area of the 2nd LCD board component.

37. LCD device as claimed in claim 34, wherein, the first end of the 2nd LCD board component aligns with the light entrance face of optical plate.

38. LCD device as claimed in claim 34, wherein, at least one in the first and second LCD board components also comprises the thin film transistor plate with thin film transistor (TFT).

39. LCD device as claimed in claim 34, wherein, at least one in the first and second LCD board components also comprises the Twisted Nematic plate.

40. LCD device as claimed in claim 34, wherein, the first and second LCD board components also comprise the driver module that is used in response to drive signal displayed image information respectively.

41. LCD device as claimed in claim 34, wherein, the one LCD board component also comprises first driver module that is used for showing in response to first drive signal first information, and the 2nd LCD board component also comprises second driver module that is used for showing in response to second drive signal second information.

42. LCD device as claimed in claim 34, wherein, the lamp assembly comprises:

Be used to produce the lamp of radial light; With

Be used for the light that lamp sends is become the lamp reflector of the first and the 5th light, this lamp reflector is fixed to the second and the 4th surface, holds lamp simultaneously therein.

Images